Mitsubishi QJ71MB91-C Modbus Interface Module for MELSEC-Q Series

The Mitsubishi QJ71MB91-C (QJ71MB91-C) is a dedicated communication interface module designed for integration within the Mitsubishi MELSEC-Q series programmable logic controller platform. Functioning as a specialized Modbus communication module, this unit enables MELSEC-Q automation systems to connect, exchange data, and interface seamlessly with third-party Modbus-compatible devices, supervisory control systems, instrumentation, and field equipment across industrial networks. Operating directly on the MELSEC-Q rack backplane, the module facilitates reliable serial communication, protocol conversion, and master or slave device networking in complex automation environments. With a recorded shipping weight of 10 kg, this assembly is engineered to provide robust performance in demanding industrial facilities, including automotive manufacturing, water treatment plants, material handling installations, and process control systems. It serves as an essential maintenance and replacement component for sustaining existing MELSEC-Q control architectures without requiring system redesigns or software overhauls. Installing the unit ensures uninterrupted data flow between Mitsubishi controllers and peripheral automation hardware, supporting long-term operational stability and predictable communication throughput across factory floor installations.